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Alcohol

Contents

  • 1 Chemistry
  • 2 Alcoholic content
  • 3 Flavoring
  • 4 History
    • 4.1 Fermented beverages
    • 4.2 Distilled beverages
  • 5 Uses
  • 6 Legal considerations
  • 7 Types of alcoholic beverages
    • 7.1 Non-distilled beverages
    • 7.2 Distilled beverages
  • 8 See also
  • 9 References
  • 10 External link

Bottles of cachaça, a Brazilian alcoholic beverage.

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Bottles of cachaça, a Brazilian alcoholic beverage.

Alcoholic beverages are drinks containing ethanol.

Alcoholic beverages have been widely consumed since prehistoric times by people around the world, seeing use as a component of the standard diet, for hygienic or medical reasons, for their relaxant and euphoric effects, for recreational purposes, for artistic inspiration, as aphrodisiacs, and for other reasons. Some have been invested with symbolic or religious significance suggesting the mystical use of alcohol, e.g., by Greco-Roman religion in the ecstatic rituals of Dionysus (also called Bacchus), god of drink and revelry; in the Christian Eucharist; and at the Jewish Passover.

Moderate consumption of alcohol, defined by the U.S. Department of Agriculture and the Dietary Guidelines for Americans as no more than two drinks for men and one drink for women per day, is consistently shown as being beneficial for the heart and circulatory system (the UK equivalent is 3-4 units per day for men and 2-3 units for women). Moderate consumers statistically have fewer heart attacks and strokes, live longer, have lower blood pressure, and generally report better overall health.

However, some people are prone to developing a chemical dependency to alcohol, alcoholism. The results of alcoholism are considered a major health problem in many nations.

Frequent excessive consumption can harmfully interfere with the user's well-being. The neurological effects of alcohol use are often a factor in deadly motor vehicle accidents and fights. People under the influence of alcohol sometimes find themselves in dangerous or compromising situations where they would not be had they remained sober. Operating a motor vehicle or heavy machinery under the influence of alcohol is a serious crime in almost all developed nations.

Some religions—most notably Islam, Latter-day Saints, the Nikaya and most Mahayana schools of Buddhism and some Protestant sects of Fundamentalist Christianity—forbid or discourage the consumption of alcoholic beverages for these and other reasons.

Most governments regulate or restrict the sale and use of alcohol.

Chemistry

The ethanol (CH3CH2OH) in alcoholic beverages is almost always produced by fermentation, which is the metabolism of carbohydrates (usually sugars) by certain species of yeast in the absence of oxygen. The process of culturing yeast under conditions that produce alcohol is referred to as brewing.

It should be noted that in chemistry, alcohol is a general term for any organic compound in which a hydroxyl group (-OH) is bound to a carbon atom, which in turn is bound to other hydrogen and/or carbon atoms. Other alcohols such as propylene glycol and the sugar alcohols may appear in food or beverages regularly, but these alcohols do not make them alcoholic.

It has been suggested that alcoholic impurities, congeners, are the cause of hangovers.

Alcoholic beverages with a concentration of about 50% ethanol or greater (100 proof) are flammable liquids and easily ignited.

Alcoholic content

The concentration of alcohol in an alcoholic beverage may be specified in percent alcohol by volume (ABV), in percentage by weight (sometimes abbreviated w/w for weight for weight), or in proof. The 'proof' measurement roughly corresponds in a 2:1 ratio to percent alcoholic content by volume (e.g. 80 proof = 40% ABV). Common distillation cannot exceed 192 proof because at that point ethanol is an azeotrope with water. Alcohols of this purity are commonly referred to as grain alcohol and are not meant for human consumption, with the notable exception of neutral grain spirits.

Most yeasts cannot grow when the concentration of alcohol is higher than about 18% by volume, so that is a practical limit for the strength of fermented beverages such as wine, beer, and sake. Strains of yeast have been developed that can survive in solutions of up to 25% alcohol by volume, but these were bred for ethanol fuel production, not beverage production. Liquors are produced by distillation of a fermented product, concentrating the alcohol and eliminating some of the by-products. Many wines are fortified wines with additional grain alcohol to achieve higher ABV than is easily reached using fermentation alone.

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